/*
 * 版权所有 ( c ) 联想集团有限公司 2005-2009 保留所有权利。
 * 项目：	Lenovo Push Service
 * 文件名：	MetadataExample.java
 * 版本:    1.0
 * 描述：	
 * 作者：	刘兵召
 * 日期：	May 10, 2010 
 * 修改历史：
 * 【时间】		【修改者】	【修改内容】
 */
package com.feng.demo.jakartacommons.sanselan;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;

import org.apache.sanselan.ImageReadException;
import org.apache.sanselan.Sanselan;
import org.apache.sanselan.common.IImageMetadata;
import org.apache.sanselan.common.RationalNumber;
import org.apache.sanselan.formats.jpeg.JpegImageMetadata;
import org.apache.sanselan.formats.tiff.TiffField;
import org.apache.sanselan.formats.tiff.TiffImageMetadata;
import org.apache.sanselan.formats.tiff.constants.TagInfo;
import org.apache.sanselan.formats.tiff.constants.TiffConstants;


public class MetadataExample {
	public static void metadataExample(File file) throws ImageReadException,
			IOException {
		// get all metadata stored in EXIF format (ie. from JPEG or TIFF).
		// org.w3c.dom.Node node = Sanselan.getMetadataObsolete(imageBytes);
		IImageMetadata metadata = Sanselan.getMetadata(file);

		// System.out.println(metadata);

		if (metadata instanceof JpegImageMetadata) {
			JpegImageMetadata jpegMetadata = (JpegImageMetadata) metadata;

			// Jpeg EXIF metadata is stored in a TIFF-based directory structure
			// and is identified with TIFF tags.
			// Here we look for the "x resolution" tag, but
			// we could just as easily search for any other tag.
			//
			// see the TiffConstants file for a list of TIFF tags.

			System.out.println("file: " + file.getPath());

			// print out various interesting EXIF tags.
			printTagValue(jpegMetadata, TiffConstants.TIFF_TAG_XRESOLUTION);
			printTagValue(jpegMetadata, TiffConstants.TIFF_TAG_DATE_TIME);
			printTagValue(jpegMetadata,TiffConstants.EXIF_TAG_DATE_TIME_ORIGINAL);
			printTagValue(jpegMetadata, TiffConstants.EXIF_TAG_CREATE_DATE);
			printTagValue(jpegMetadata, TiffConstants.EXIF_TAG_ISO);
			printTagValue(jpegMetadata,TiffConstants.EXIF_TAG_SHUTTER_SPEED_VALUE);
			printTagValue(jpegMetadata, TiffConstants.EXIF_TAG_APERTURE_VALUE);
			printTagValue(jpegMetadata, TiffConstants.EXIF_TAG_BRIGHTNESS_VALUE);
			printTagValue(jpegMetadata, TiffConstants.GPS_TAG_GPS_LATITUDE_REF);
			printTagValue(jpegMetadata, TiffConstants.GPS_TAG_GPS_LATITUDE);
			printTagValue(jpegMetadata, TiffConstants.GPS_TAG_GPS_LONGITUDE_REF);
			printTagValue(jpegMetadata, TiffConstants.GPS_TAG_GPS_LONGITUDE);

			System.out.println();

			// simple interface to GPS data
			TiffImageMetadata exifMetadata = jpegMetadata.getExif();
			if (null != exifMetadata) {
				TiffImageMetadata.GPSInfo gpsInfo = exifMetadata.getGPS();
				if (null != gpsInfo) {
					String gpsDescription = gpsInfo.toString();
					double longitude = gpsInfo.getLongitudeAsDegreesEast();
					double latitude = gpsInfo.getLatitudeAsDegreesNorth();

					System.out.println("	" + "GPS Description: "
							+ gpsDescription);
					System.out.println("	" + "GPS Longitude (Degrees East): "
							+ longitude);
					System.out.println("	" + "GPS Latitude (Degrees North): "
							+ latitude);
				}
			}

			// more specific example of how to manually access GPS values
			TiffField gpsLatitudeRefField = jpegMetadata
					.findEXIFValueWithExactMatch(TiffConstants.GPS_TAG_GPS_LATITUDE_REF);
			TiffField gpsLatitudeField = jpegMetadata
					.findEXIFValueWithExactMatch(TiffConstants.GPS_TAG_GPS_LATITUDE);
			TiffField gpsLongitudeRefField = jpegMetadata
					.findEXIFValueWithExactMatch(TiffConstants.GPS_TAG_GPS_LONGITUDE_REF);
			TiffField gpsLongitudeField = jpegMetadata
					.findEXIFValueWithExactMatch(TiffConstants.GPS_TAG_GPS_LONGITUDE);
			if (gpsLatitudeRefField != null && gpsLatitudeField != null
					&& gpsLongitudeRefField != null
					&& gpsLongitudeField != null) {
				// all of these values are strings.
				String gpsLatitudeRef = (String) gpsLatitudeRefField.getValue();
				RationalNumber gpsLatitude[] = (RationalNumber[]) (gpsLatitudeField
						.getValue());
				String gpsLongitudeRef = (String) gpsLongitudeRefField
						.getValue();
				RationalNumber gpsLongitude[] = (RationalNumber[]) gpsLongitudeField
						.getValue();

				RationalNumber gpsLatitudeDegrees = gpsLatitude[0];
				RationalNumber gpsLatitudeMinutes = gpsLatitude[1];
				RationalNumber gpsLatitudeSeconds = gpsLatitude[2];

				RationalNumber gpsLongitudeDegrees = gpsLongitude[0];
				RationalNumber gpsLongitudeMinutes = gpsLongitude[1];
				RationalNumber gpsLongitudeSeconds = gpsLongitude[2];

				// This will format the gps info like so:
				//
				// gpsLatitude: 8 degrees, 40 minutes, 42.2 seconds S
				// gpsLongitude: 115 degrees, 26 minutes, 21.8 seconds E

				System.out.println("	" + "GPS Latitude: "
						+ gpsLatitudeDegrees.toDisplayString() + " degrees, "
						+ gpsLatitudeMinutes.toDisplayString() + " minutes, "
						+ gpsLatitudeSeconds.toDisplayString() + " seconds "
						+ gpsLatitudeRef);
				System.out.println("	" + "GPS Longitude: "
						+ gpsLongitudeDegrees.toDisplayString() + " degrees, "
						+ gpsLongitudeMinutes.toDisplayString() + " minutes, "
						+ gpsLongitudeSeconds.toDisplayString() + " seconds "
						+ gpsLongitudeRef);

			}

			System.out.println();

			ArrayList items = jpegMetadata.getItems();
			for (int i = 0; i < items.size(); i++) {
				Object item = items.get(i);
				System.out.println("	" + "item: " + item);
			}

			System.out.println();
		}
	}

	private static void printTagValue(JpegImageMetadata jpegMetadata,
			TagInfo tagInfo) throws ImageReadException, IOException {
		TiffField field = jpegMetadata.findEXIFValueWithExactMatch(tagInfo);
		if (field == null)
			System.out.println(tagInfo.name + ": " + "Not Found.");
		else
			System.out.println(tagInfo.name + ": "field.getValueDescription());
	}

}
